Foursevens Quark Tactical QT2L-X Burst Mode review

SCEMan

SCEMan

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Awesome review ti-force!
Your runtime charts are exactly what is needed :thumbsup:
 
CampingMaster

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I have the Foursevens Quark Tactical QT2L-X with Burst Mode here for review. This light was sent to me by Foursevens for review purposes. If you haven't seen my Quark X 123-2 review, you can see it here- click


For those of you who may not have heard, Foursevens has upgraded their popular QT2L-X by upgrading the circuitry to produce a massive amount of light in Max mode. Follow along to see just how much the light output in Max mode was increased compared to the QT2L-X non-Burst Mode.

And here it is directly compared to the previous Quark X without Burst Mode-

QuarkXvsQT2L-XBurtModeOTFLumengraph.png


In closing, I’m very impressed with this light. Not only does it output a tremendous amount of light in such a small form factor, it retains a very useable and long runtime in Max mode. For those of you who need (or want) large amounts of light in a small form factor, this is your light. Thanks for reading, and I hope you enjoyed my review.


FIRST INTERROGATION :


1.- If the QP2L-X has 500 lumens for 3 min before stabilizing at 360 lumens.


2.- and the QP2L-X with Burst has 800 lumens for 1 min before stabilizing at 410 lumens


3.- with this info should I expect my QP2L-X gen 2 to have 600 lumens for 3 min and stabilize at 430 lumens ( 360 X 20% ) ?


 

SECOND INTERROGATION :


1.- « Studies have shown that since the eye perceives light intensity on a logarithmic scale, it actually takes four times the output for the eyes to see double the output. » -- Quoted from FOURSEVENS email.


A.- Based on this info what will be the difference live between the 800 lumens QP2L-X with Burst and my QP2L-X gen 2 with probably 600 lumens for the first 3 min ? Any ?


B.- And also what will be de difference between the QP2L-X with Burst with a maximum of 410 lumens and the expected maximum of 430+​ lumens with the QP2L-X gen 2 ( 360 + 20% ) ? Any ?


 

THIRD INTERROGATION :


1.- « The difference between the full output of the Burst mode and 50% of Burst mode will not be that significant but runtime will more than double. » -- Quoted from FOURSEVENS email.


A.- Based on this info why the QP2L-X with Burst has a High at 300 lumens and the maximum is at 390 lumens ; the difference is so minimal that we won't see any difference except for the runtime ? My QP2L-X gen 2 has a High of 160 lumens from 65 but for the QP2L-X with Burst the jump is from 55 lumens to 300...


I don't see why I should buy the QP2L-X with Burst having already something hard to beat with the QP2L-X gen 2.


Is somebody can explain me what I am missing, what I don't understand, or is my way of thinking has something good ? Thank you very much. I don't know what's happening but my Enter key does'nt work at all in the forum. This is the first time I see this happening. I hope you will understand my thinking because I write with a french accent...
 
Last edited:
ti-force

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FIRST INTERROGATION :


1.- If the QP2L-X has 500 lumens for 3 min before stabilizing at 360 lumens.


2.- and the QP2L-X with Burst has 800 lumens for 1 min before stabilizing at 410 lumens


3.- with this info should I expect my QP2L-X gen 2 to have 600 lumens for 3 min and stabilize at 430 lumens ( 360 X 20% ) ?


 

SECOND INTERROGATION :


1.- « Studies have shown that since the eye perceives light intensity on a logarithmic scale, it actually takes four times the output for the eyes to see double the output. » -- Quoted from FOURSEVENS email.


A.- Based on this info what will be the difference live between the 800 lumens QP2L-X with Burst and my QP2L-X gen 2 with probably 600 lumens for the first 3 min ? Any ?


B.- And also what will be de difference between the QP2L-X with Burst with a maximum of 410 lumens and the expected maximum of 430+​ lumens with the QP2L-X gen 2 ( 360 + 20% ) ? Any ?


 

THIRD INTERROGATION :


1.- « The difference between the full output of the Burst mode and 50% of Burst mode will not be that significant but runtime will more than double. » -- Quoted from FOURSEVENS email.


A.- Based on this info why the QP2L-X with Burst has a High at 300 lumens and the maximum is at 390 lumens ; the difference is so minimal that we won't see any difference except for the runtime ? My QP2L-X gen 2 has a High of 160 lumens from 65 but for the QP2L-X with Burst the jump is from 55 lumens to 300...


I don't see why I should buy the QP2L-X with Burst having already something hard to beat with the QP2L-X gen 2.


Is somebody can explain me what I am missing, what I don't understand, or is my way of thinking has something good ? Thank you very much. I don't know what's happening but my Enter key does'nt work at all in the forum. This is the first time I see this happening. I hope you will understand my thinking because I write with a french accent...



First interrogation I can't really answer because I haven't tested a gen 2 light, or even held one in person.

Second interrogation.
A. If gen 2 makes 600 and the new burst mode makes roughly 800, the difference is roughly 200 lumens ;) jk, jk. I don't how to explain the difference to you. If you have a light that makes roughly 200 lumens, turn it on and look at it. That would be about the amount of increase in light. Then maybe turn on both the 200 lumen light (preferably a Quark with wide beam angle) and the 600 lumen light and combine the beams together, then separate, then together again. Maybe that will give you a rough idea of what to expect. Now whether you need (or want) that increase in light is up to you.

B. Null. My opinion you wouldn't notice that small difference.
 
Coolz

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Great review! Just wondered if anyone has tested this with the tried and true 18650 body. I *think* I read somewhere that it works, but I can't seem to verify that information.
 
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reppans

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I don't see why I should buy the QP2L-X with Burst having already something hard to beat with the QP2L-X gen 2.

Is somebody can explain me what I am missing, what I don't understand, or is my way of thinking has something good ?

Except for adding 20% for the G2 emitter (that's marketing max benefit - SB tested closer to ~10% OTF bump), I think your analysis is good. I believe in the logarithmic visual perception thing where we'll perceive the square root of lumen increases, while power consumption is linear to lumen changes. That's how I have become a low lumen fanatic (ie, I get 4x the runtime for half the perceived brightness) - if going up the lumen scale is subject to the laws of diminishing returns, then going down is subject to increasing gains. And Quarks are excellent on the low end, and why I personally love them.

If you double output from 400 to 800 lumens it will be perceived as ~ 41% increase to your eyes (square root of 2 = 1.41). That's enough to be noticeable, but it won't feel as much as it sounds.... except to the battery, of course. Also, if you tend to use turbo mode like most people, in short sub-minute bursts, then your cumulative runtime on turbo will actually be closer to half the listed spec.... something to consider.

The bottom line is that only you can decide when to upgrade. Just like iPhone upgrades going for 3G to 3GS to 4 to 4S to 5 etc, it may not make sense to upgrade at every iteration, perhaps just wait, enjoy what you're using, and catch it the next time around.
 
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wrj0

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Terrifically thorough and detailed review. Thank you! Helped me decide that I really do need one.
 
recDNA

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Any pre_flash in this one?

Sent from my DROID RAZR HD using Tapatalk 2
 
ti-force

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Any pre_flash in this one?

Sent from my DROID RAZR HD using Tapatalk 2

No pre-flash here either. If memory serves correctly, I think Foursevens made changes to eliminate pre-flash back when they released the first Quark X.
 
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Etsu

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No pre-flash here either. If memory serves correctly, I think Foursevens made changes to eliminate pre-flash back when they released the first Quark X.

They weren't very successful at it, then. I bought a Quark QP2A-X (XML2 version) a couple of months ago, and there's definite pre-flash on moonlight mode. It's brief, not annoying bright, but it's definitely there.

There's none on my Preon. So, maybe it's only a problem with moonlight modes that are current-regulated, not PWM.
 
ti-force

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They weren't very successful at it, then. I bought a Quark QP2A-X (XML2 version) a couple of months ago, and there's definite pre-flash on moonlight mode. It's brief, not annoying bright, but it's definitely there.

There's none on my Preon. So, maybe it's only a problem with moonlight modes that are current-regulated, not PWM.

Maybe we should define pre-flash just to make sure we're on the same page. When I hear (or see) pre-flash mentioned I immediately think of it as selecting a lower output mode (e.g., moonlight) and immediately when the light is turned on the user gets an extremely bright flash that completely ruins ones night vision temporarily until ones eyes can readjust. But pre-flash could simply be an immediate flash that's dimmer than the selected modes output, correct? I've tested the first Quark x's (2x Cr123a and 2x aa) for pre-flash and have noticed a pre-flash that is dimmer than and/or the same brightness as moonlight mode immediately when the light is turned on. It's more like a flicker than a flash, and it happens so quickly that I hardly even noticed it. Is this what you're talking about or do you get an actual bright flash that takes away from your eyes adjustment to low light levels?
 
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Etsu

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I get a bright flash, before the light goes down to moonlight brightness. It's very quick, and it doesn't affect my night vision, so I don't find it a problem. It's hard to estimate how bright the flash is. Probably something around 5 lumens, but that's just a guess. It only lasts for maybe 10 milliseconds. It's quick enough that I sometimes don't notice it. (A blink is longer.) It doesn't seem to matter how long the flashlight has been off, or the charge-level of the batteries. I just consider it a minor quirk that doesn't bother me. If it was a lot brighter, I might consider it to be an issue.
 
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passive101

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I'm interested in the Pro model like this. Does it take 18650 batteries if not, why the heck not, the are around 1mm difference and 18650 is now a very normal standard battery size.
 
AnAppleSnail

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I'm interested in the Pro model like this. Does it take 18650 batteries if not, why the heck not, the are around 1mm difference and 18650 is now a very normal standard battery size.

Thread size. The Quark standard lego threads just don't fit a 19690 (Let's be honest about sizes, 19mm diameter and 69mm length are required in the battery compartment) battery. The limited-run '18650 body' actually was a complete compartment because it had to have thread of smaller diameter than the hollow core for the battery to sit in.
 
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passive101

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I'm surprised that Foursevens doesn't really support 18650 batteries in their lights. I thought they were on top of the battery scene pretty well.
 
Overclocker

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I'm surprised that Foursevens doesn't really support 18650 batteries in their lights. I thought they were on top of the battery scene pretty well.


quarks were designed to be quite small and lego-able so naturally 18650 is too fat for them. so just use the 16650 or 17670

their larger MMX and MMS are 18650 compatible
 
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passive101

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quarks were designed to be quite small and lego-able so naturally 18650 is too fat for them. so just use the 16650 or 17670

their larger MMX and MMS are 18650 compatible

Why don't they just make an optional 18650 body people can buy? 18650 is a standard that is 2x123A compatible and 18650 batteries can be purchased by the flashlights in Cabela's and Gander Mountain. I can't however purchase 16650 or 17670.
 
AnAppleSnail

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Why don't they just make an optional 18650 body people can buy? 18650 is a standard that is 2x123A compatible and 18650 batteries can be purchased by the flashlights in Cabela's and Gander Mountain. I can't however purchase 16650 or 17670.

They did. But it's a complicated part that's expensive to build and not very cost effective. There are a few hundred in the world. (Read my post above yours).
 
Overclocker

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exactly. 18650 is just too fat for the quarks. don't expect a slim AA/CR123 light to be able to accommodate 18650. the excellent sanyo 16650 2100mah cell is readily available from a variety of online dealers and it's what i use on my QP2L-X
 

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